The aim of this study was to determine the associations between vascular endothelial function, intima-media thickness (IMT) of the common carotid artery and anthropometric/metabolic parameters in healthy obese women without obesity-related metabolic complications and age-matched healthy lean controls. Twenty-four obese [body mass index (BMI) >30 kg/m(2); age 31.4+/-7.4 yr] and 14 lean (BMI <24 kg/m(2); age 30.5+/-7.2 yr) women were studied. All of the subjects had normolipemia. Insulin resistance was calculated according to the homeostasis model assessment (HOMA) formula. Endothelial function was measured by flow-mediated dilation (FMD) of the brachial artery. IMT of the common carotid artery was calculated from high-resolution ultrasound imaging of the two common carotid arteries. Obese and lean women were matched with respect to age, smoking status, blood pressure, glucose, insulin concentrations and HOMA. IMT of common carotid artery was significantly higher (0.56+/-0.09 vs 0.45+/-0.06 mm,p<0.001) and FMD (percentage of change from baseline) was significantly lower (13.3+/-6.5% vs 25.2+/-13.9%,p<0.001) in the obese subjects. Lipid profile, blood pressure, indirect measurement of insulin resistance, leptin concentrations and anthropometric parameters did not predict the FMD or IMT in the obese and lean groups. It is concluded that even in healthy obese women with a normal metabolic profile, deterioration in endothelial function and early atherosclerotic changes are evident compared with healthy lean counterparts. Some undetermined factors in our study other than obesity-related well-known risk factors could be responsible for this observation. (C) 2003, Editrice Kurtis.